Engines, for example vehicle engines, have included aspirators and/or check valves for a long time. Typically, the aspirators are used to generate a vacuum that is lower than engine manifold vacuum by inducing some of the engine air to travel through a Venturi gap. The aspirators may include check valves therein or the system may include separate check valves.
Good flow performance of a check valve includes quick response, opening against a small pressure difference, closing against a small pressure difference, and low resistance to flow over all operating temperatures. Depending on the combination of operating temperatures, material for the check valve, and the pressure differential acting on the check valve, the sealing member will contact a variety of features in the open position and the closed position, and experience stress as a result thereof. This stress can, over time and variation in operating conditions, cause degradation of the surface of the sealing member and/or internal failure of the sealing member. Improvements are needed for check valves under operating conditions that induce high forces onto the check valve as a result of the pressure differences across it to extend the life of the sealing member and the overall life of the check valve.